diff --git a/core/includes/errors.inc b/core/includes/errors.inc
index b96b8281dd5c62b3e8ab780e8b4c09229e3e84c2..e3ad1c89e1743454453b9ebc416b33649f1e6a2e 100644
--- a/core/includes/errors.inc
+++ b/core/includes/errors.inc
@@ -80,6 +80,7 @@ function _drupal_error_handler_real($error_level, $message, $filename, $line, $c
       '%line' => $caller['line'],
       'severity_level' => $severity_level,
       'backtrace' => $backtrace,
+      '@backtrace_string' => (new \Exception())->getTraceAsString(),
     ), $recoverable || $to_string);
   }
 }
@@ -116,9 +117,9 @@ function error_displayable($error = NULL) {
  *
  * @param $error
  *   An array with the following keys: %type, @message, %function, %file,
- *   %line, severity_level, and backtrace. All the parameters are plain-text,
- *   with the exception of @message, which needs to be an HTML string, and
- *   backtrace, which is a standard PHP backtrace.
+ *   %line, @backtrace_string, severity_level, and backtrace. All the parameters
+ *   are plain-text, with the exception of @message, which needs to be an HTML
+ *   string, and backtrace, which is a standard PHP backtrace.
  * @param bool $fatal
  *   TRUE for:
  *   - An exception is thrown and not caught by something else.
@@ -163,18 +164,18 @@ function _drupal_log_error($error, $fatal = FALSE) {
   // installer.
   if (\Drupal::hasService('logger.factory')) {
     try {
-      \Drupal::logger('php')->log($error['severity_level'], '%type: @message in %function (line %line of %file).', $error);
+      \Drupal::logger('php')->log($error['severity_level'], '%type: @message in %function (line %line of %file) @backtrace_string.', $error);
     }
     catch (\Exception $e) {
       // We can't log, for example because the database connection is not
       // available. At least try to log to PHP error log.
-      error_log(strtr('Failed to log error: %type: @message in %function (line %line of %file).', $error));
+      error_log(strtr('Failed to log error: %type: @message in %function (line %line of %file). @backtrace_string', $error));
     }
   }
 
   // Log fatal errors, so developers can find and debug them.
   if ($fatal) {
-    error_log(sprintf('%s: %s in %s on line %d', $error['%type'], $error['@message'], $error['%file'], $error['%line']));
+    error_log(sprintf('%s: %s in %s on line %d %s', $error['%type'], $error['@message'], $error['%file'], $error['%line'], $error['@backtrace_string']));
   }
 
   if (PHP_SAPI === 'cli') {
diff --git a/core/lib/Drupal/Core/Utility/Error.php b/core/lib/Drupal/Core/Utility/Error.php
index aca31fae837ffec6c238c4189d5286b8e990d739..6105a59021cbc06388b8cf7e6a382ec95351bddc 100644
--- a/core/lib/Drupal/Core/Utility/Error.php
+++ b/core/lib/Drupal/Core/Utility/Error.php
@@ -71,7 +71,7 @@ public static function decodeException($exception) {
       '%line' => $caller['line'],
       'severity_level' => static::ERROR,
       'backtrace' => $backtrace,
-      'backtrace_string' => $exception->getTraceAsString(),
+      '@backtrace_string' => $exception->getTraceAsString(),
     );
   }
 
diff --git a/core/modules/system/src/Tests/System/UncaughtExceptionTest.php b/core/modules/system/src/Tests/System/UncaughtExceptionTest.php
index 0cc68627a5b4fa1981268fefa3ffba8c38d2a90c..c155781d518d529a177fda62121d8689f0278c54 100644
--- a/core/modules/system/src/Tests/System/UncaughtExceptionTest.php
+++ b/core/modules/system/src/Tests/System/UncaughtExceptionTest.php
@@ -253,7 +253,7 @@ public function testLoggerException() {
 
     // Find fatal error logged to the simpletest error.log
     $errors = file(\Drupal::root() . '/' . $this->siteDirectory . '/error.log');
-    $this->assertIdentical(count($errors), 2, 'The error + the error that the logging service is broken has been written to the error log.');
+    $this->assertIdentical(count($errors), 8, 'The error + the error that the logging service is broken has been written to the error log.');
     $this->assertTrue(strpos($errors[0], 'Failed to log error') !== FALSE, 'The error handling logs when an error could not be logged to the logger.');
 
     $expected_path = \Drupal::root() . '/core/modules/system/tests/modules/error_service_test/src/MonkeysInTheControlRoom.php';